block_map.rs

   1use super::wrap_map::{self, WrapEdit, WrapPoint, WrapSnapshot};
   2use crate::{Anchor, ToPoint as _};
   3use collections::{HashMap, HashSet};
   4use gpui::{AppContext, ElementBox};
   5use language::{BufferSnapshot, Chunk};
   6use parking_lot::Mutex;
   7use std::{
   8    cmp::{self, Ordering, Reverse},
   9    fmt::Debug,
  10    ops::{Deref, Range},
  11    path::Path,
  12    sync::{
  13        atomic::{AtomicUsize, Ordering::SeqCst},
  14        Arc,
  15    },
  16};
  17use sum_tree::{Bias, SumTree};
  18use text::{Edit, Point};
  19
  20const NEWLINES: &'static [u8] = &[b'\n'; u8::MAX as usize];
  21
  22pub struct BlockMap {
  23    next_block_id: AtomicUsize,
  24    wrap_snapshot: Mutex<WrapSnapshot>,
  25    blocks: Vec<Arc<Block>>,
  26    transforms: Mutex<SumTree<Transform>>,
  27}
  28
  29pub struct BlockMapWriter<'a>(&'a mut BlockMap);
  30
  31pub struct BlockSnapshot {
  32    wrap_snapshot: WrapSnapshot,
  33    transforms: SumTree<Transform>,
  34}
  35
  36#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
  37pub struct BlockId(usize);
  38
  39#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  40pub struct BlockPoint(pub super::Point);
  41
  42#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  43struct BlockRow(u32);
  44
  45#[derive(Copy, Clone, Debug, Default, Eq, Ord, PartialOrd, PartialEq)]
  46struct WrapRow(u32);
  47
  48pub type RenderBlock = Arc<dyn Fn(&BlockContext) -> ElementBox>;
  49
  50pub struct Block {
  51    id: BlockId,
  52    position: Anchor,
  53    height: u8,
  54    render: Mutex<RenderBlock>,
  55    disposition: BlockDisposition,
  56}
  57
  58#[derive(Clone)]
  59pub struct BlockProperties<P>
  60where
  61    P: Clone,
  62{
  63    pub position: P,
  64    pub height: u8,
  65    pub render: Arc<dyn Fn(&BlockContext) -> ElementBox>,
  66    pub disposition: BlockDisposition,
  67}
  68
  69pub struct BlockContext<'a> {
  70    pub cx: &'a AppContext,
  71    pub anchor_x: f32,
  72    pub scroll_x: f32,
  73    pub gutter_width: f32,
  74    pub gutter_padding: f32,
  75    pub em_width: f32,
  76    pub line_height: f32,
  77}
  78
  79#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
  80pub enum BlockDisposition {
  81    Above,
  82    Below,
  83}
  84
  85#[derive(Clone, Debug)]
  86struct Transform {
  87    summary: TransformSummary,
  88    block: Option<TransformBlock>,
  89}
  90
  91#[derive(Clone)]
  92enum TransformBlock {
  93    Custom {
  94        block: Arc<Block>,
  95        column: u32,
  96    },
  97    ExcerptHeader {
  98        buffer: BufferSnapshot,
  99        range: Range<text::Anchor>,
 100        path: Option<Arc<Path>>,
 101    },
 102}
 103
 104impl TransformBlock {
 105    fn disposition(&self) -> BlockDisposition {
 106        match self {
 107            TransformBlock::Custom { block, column } => block.disposition,
 108            TransformBlock::ExcerptHeader { .. } => BlockDisposition::Above,
 109        }
 110    }
 111}
 112
 113impl Debug for TransformBlock {
 114    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 115        match self {
 116            Self::Custom { block, column } => f
 117                .debug_struct("Custom")
 118                .field("block", block)
 119                .field("column", column)
 120                .finish(),
 121            Self::ExcerptHeader { buffer, path, .. } => {
 122                f.debug_struct("ExcerptHeader").field("path", path).finish()
 123            }
 124        }
 125    }
 126}
 127
 128#[derive(Clone, Debug, Default)]
 129struct TransformSummary {
 130    input_rows: u32,
 131    output_rows: u32,
 132}
 133
 134pub struct BlockChunks<'a> {
 135    transforms: sum_tree::Cursor<'a, Transform, (BlockRow, WrapRow)>,
 136    input_chunks: wrap_map::WrapChunks<'a>,
 137    input_chunk: Chunk<'a>,
 138    output_row: u32,
 139    max_output_row: u32,
 140}
 141
 142pub struct BlockBufferRows<'a> {
 143    transforms: sum_tree::Cursor<'a, Transform, (BlockRow, WrapRow)>,
 144    input_buffer_rows: wrap_map::WrapBufferRows<'a>,
 145    output_row: u32,
 146    started: bool,
 147}
 148
 149impl BlockMap {
 150    pub fn new(wrap_snapshot: WrapSnapshot) -> Self {
 151        Self {
 152            next_block_id: AtomicUsize::new(0),
 153            blocks: Vec::new(),
 154            transforms: Mutex::new(SumTree::from_item(
 155                Transform::isomorphic(wrap_snapshot.text_summary().lines.row + 1),
 156                &(),
 157            )),
 158            wrap_snapshot: Mutex::new(wrap_snapshot),
 159        }
 160    }
 161
 162    pub fn read(&self, wrap_snapshot: WrapSnapshot, edits: Vec<WrapEdit>) -> BlockSnapshot {
 163        self.sync(&wrap_snapshot, edits);
 164        *self.wrap_snapshot.lock() = wrap_snapshot.clone();
 165        BlockSnapshot {
 166            wrap_snapshot,
 167            transforms: self.transforms.lock().clone(),
 168        }
 169    }
 170
 171    pub fn write(&mut self, wrap_snapshot: WrapSnapshot, edits: Vec<WrapEdit>) -> BlockMapWriter {
 172        self.sync(&wrap_snapshot, edits);
 173        *self.wrap_snapshot.lock() = wrap_snapshot;
 174        BlockMapWriter(self)
 175    }
 176
 177    fn sync(&self, wrap_snapshot: &WrapSnapshot, edits: Vec<WrapEdit>) {
 178        if edits.is_empty() {
 179            return;
 180        }
 181
 182        let buffer = wrap_snapshot.buffer_snapshot();
 183        let mut transforms = self.transforms.lock();
 184        let mut new_transforms = SumTree::new();
 185        let old_row_count = transforms.summary().input_rows;
 186        let new_row_count = wrap_snapshot.max_point().row() + 1;
 187        let mut cursor = transforms.cursor::<WrapRow>();
 188        let mut last_block_ix = 0;
 189        let mut blocks_in_edit = Vec::new();
 190        let mut edits = edits.into_iter().peekable();
 191
 192        while let Some(edit) = edits.next() {
 193            // Preserve any old transforms that precede this edit.
 194            let old_start = WrapRow(edit.old.start);
 195            let new_start = WrapRow(edit.new.start);
 196            new_transforms.push_tree(cursor.slice(&old_start, Bias::Left, &()), &());
 197            if let Some(transform) = cursor.item() {
 198                if transform.is_isomorphic() && old_start == cursor.end(&()) {
 199                    new_transforms.push(transform.clone(), &());
 200                    cursor.next(&());
 201                    while let Some(transform) = cursor.item() {
 202                        if transform
 203                            .block
 204                            .as_ref()
 205                            .map_or(false, |b| b.disposition.is_below())
 206                        {
 207                            new_transforms.push(transform.clone(), &());
 208                            cursor.next(&());
 209                        } else {
 210                            break;
 211                        }
 212                    }
 213                }
 214            }
 215
 216            // Preserve any portion of an old transform that precedes this edit.
 217            let extent_before_edit = old_start.0 - cursor.start().0;
 218            push_isomorphic(&mut new_transforms, extent_before_edit);
 219
 220            // Skip over any old transforms that intersect this edit.
 221            let mut old_end = WrapRow(edit.old.end);
 222            let mut new_end = WrapRow(edit.new.end);
 223            cursor.seek(&old_end, Bias::Left, &());
 224            cursor.next(&());
 225            if old_end == *cursor.start() {
 226                while let Some(transform) = cursor.item() {
 227                    if transform
 228                        .block
 229                        .as_ref()
 230                        .map_or(false, |b| b.disposition.is_below())
 231                    {
 232                        cursor.next(&());
 233                    } else {
 234                        break;
 235                    }
 236                }
 237            }
 238
 239            // Combine this edit with any subsequent edits that intersect the same transform.
 240            while let Some(next_edit) = edits.peek() {
 241                if next_edit.old.start <= cursor.start().0 {
 242                    old_end = WrapRow(next_edit.old.end);
 243                    new_end = WrapRow(next_edit.new.end);
 244                    cursor.seek(&old_end, Bias::Left, &());
 245                    cursor.next(&());
 246                    if old_end == *cursor.start() {
 247                        while let Some(transform) = cursor.item() {
 248                            if transform
 249                                .block
 250                                .as_ref()
 251                                .map_or(false, |b| b.disposition.is_below())
 252                            {
 253                                cursor.next(&());
 254                            } else {
 255                                break;
 256                            }
 257                        }
 258                    }
 259                    edits.next();
 260                } else {
 261                    break;
 262                }
 263            }
 264
 265            // Find the blocks within this edited region.
 266            let new_buffer_start =
 267                wrap_snapshot.to_point(WrapPoint::new(new_start.0, 0), Bias::Left);
 268            let start_anchor = buffer.anchor_before(new_buffer_start);
 269            let start_block_ix = match self.blocks[last_block_ix..].binary_search_by(|probe| {
 270                probe
 271                    .position
 272                    .cmp(&start_anchor, &buffer)
 273                    .unwrap()
 274                    .then(Ordering::Greater)
 275            }) {
 276                Ok(ix) | Err(ix) => last_block_ix + ix,
 277            };
 278
 279            let end_anchor;
 280            let end_block_ix = if new_end.0 > wrap_snapshot.max_point().row() {
 281                end_anchor = Anchor::max();
 282                self.blocks.len()
 283            } else {
 284                let new_buffer_end =
 285                    wrap_snapshot.to_point(WrapPoint::new(new_end.0, 0), Bias::Left);
 286                end_anchor = buffer.anchor_before(new_buffer_end);
 287                match self.blocks[start_block_ix..].binary_search_by(|probe| {
 288                    probe
 289                        .position
 290                        .cmp(&end_anchor, &buffer)
 291                        .unwrap()
 292                        .then(Ordering::Greater)
 293                }) {
 294                    Ok(ix) | Err(ix) => start_block_ix + ix,
 295                }
 296            };
 297            last_block_ix = end_block_ix;
 298
 299            debug_assert!(blocks_in_edit.is_empty());
 300            blocks_in_edit.extend(
 301                self.blocks[start_block_ix..end_block_ix]
 302                    .iter()
 303                    .map(|block| {
 304                        let mut position = block.position.to_point(&buffer);
 305                        let column = wrap_snapshot.from_point(position, Bias::Left).column();
 306                        match block.disposition {
 307                            BlockDisposition::Above => position.column = 0,
 308                            BlockDisposition::Below => {
 309                                position.column = buffer.line_len(position.row)
 310                            }
 311                        }
 312                        let position = wrap_snapshot.from_point(position, Bias::Left);
 313                        (
 314                            position.row(),
 315                            TransformBlock::Custom {
 316                                block: block.clone(),
 317                                column,
 318                            },
 319                        )
 320                    }),
 321            );
 322            blocks_in_edit.extend(
 323                buffer
 324                    .excerpt_boundaries_in_range(start_anchor..end_anchor)
 325                    .map(|excerpt_boundary| {
 326                        (
 327                            excerpt_boundary.row,
 328                            TransformBlock::ExcerptHeader {
 329                                buffer: excerpt_boundary.buffer,
 330                                range: excerpt_boundary.range,
 331                                path: excerpt_boundary.path,
 332                            },
 333                        )
 334                    }),
 335            );
 336
 337            // When multiple blocks are on the same row, newer blocks appear above older
 338            // blocks. This is arbitrary, but we currently rely on it in ProjectDiagnosticsEditor.
 339            blocks_in_edit.sort();
 340
 341            // For each of these blocks, insert a new isomorphic transform preceding the block,
 342            // and then insert the block itself.
 343            for (block_row, block) in blocks_in_edit.drain(..) {
 344                let insertion_row = match block.disposition() {
 345                    BlockDisposition::Above => block_row,
 346                    BlockDisposition::Below => block_row + 1,
 347                };
 348                let extent_before_block = insertion_row - new_transforms.summary().input_rows;
 349                push_isomorphic(&mut new_transforms, extent_before_block);
 350                new_transforms.push(Transform::block(block), &());
 351            }
 352
 353            old_end = WrapRow(old_end.0.min(old_row_count));
 354            new_end = WrapRow(new_end.0.min(new_row_count));
 355
 356            // Insert an isomorphic transform after the final block.
 357            let extent_after_last_block = new_end.0 - new_transforms.summary().input_rows;
 358            push_isomorphic(&mut new_transforms, extent_after_last_block);
 359
 360            // Preserve any portion of the old transform after this edit.
 361            let extent_after_edit = cursor.start().0 - old_end.0;
 362            push_isomorphic(&mut new_transforms, extent_after_edit);
 363        }
 364
 365        new_transforms.push_tree(cursor.suffix(&()), &());
 366        debug_assert_eq!(
 367            new_transforms.summary().input_rows,
 368            wrap_snapshot.max_point().row() + 1
 369        );
 370
 371        drop(cursor);
 372        *transforms = new_transforms;
 373    }
 374
 375    pub fn replace(&mut self, mut renderers: HashMap<BlockId, RenderBlock>) {
 376        for block in &self.blocks {
 377            if let Some(render) = renderers.remove(&block.id) {
 378                *block.render.lock() = render;
 379            }
 380        }
 381    }
 382}
 383
 384fn push_isomorphic(tree: &mut SumTree<Transform>, rows: u32) {
 385    if rows == 0 {
 386        return;
 387    }
 388
 389    let mut extent = Some(rows);
 390    tree.update_last(
 391        |last_transform| {
 392            if last_transform.is_isomorphic() {
 393                let extent = extent.take().unwrap();
 394                last_transform.summary.input_rows += extent;
 395                last_transform.summary.output_rows += extent;
 396            }
 397        },
 398        &(),
 399    );
 400    if let Some(extent) = extent {
 401        tree.push(Transform::isomorphic(extent), &());
 402    }
 403}
 404
 405impl BlockPoint {
 406    pub fn new(row: u32, column: u32) -> Self {
 407        Self(Point::new(row, column))
 408    }
 409}
 410
 411impl Deref for BlockPoint {
 412    type Target = Point;
 413
 414    fn deref(&self) -> &Self::Target {
 415        &self.0
 416    }
 417}
 418
 419impl std::ops::DerefMut for BlockPoint {
 420    fn deref_mut(&mut self) -> &mut Self::Target {
 421        &mut self.0
 422    }
 423}
 424
 425impl<'a> BlockMapWriter<'a> {
 426    pub fn insert(
 427        &mut self,
 428        blocks: impl IntoIterator<Item = BlockProperties<Anchor>>,
 429    ) -> Vec<BlockId> {
 430        let mut ids = Vec::new();
 431        let mut edits = Vec::<Edit<u32>>::new();
 432        let wrap_snapshot = &*self.0.wrap_snapshot.lock();
 433        let buffer = wrap_snapshot.buffer_snapshot();
 434
 435        for block in blocks {
 436            let id = BlockId(self.0.next_block_id.fetch_add(1, SeqCst));
 437            ids.push(id);
 438
 439            let position = block.position;
 440            let point = position.to_point(&buffer);
 441            let wrap_row = wrap_snapshot
 442                .from_point(Point::new(point.row, 0), Bias::Left)
 443                .row();
 444            let start_row = wrap_snapshot.prev_row_boundary(WrapPoint::new(wrap_row, 0));
 445            let end_row = wrap_snapshot
 446                .next_row_boundary(WrapPoint::new(wrap_row, 0))
 447                .unwrap_or(wrap_snapshot.max_point().row() + 1);
 448
 449            let block_ix = match self
 450                .0
 451                .blocks
 452                .binary_search_by(|probe| probe.position.cmp(&position, &buffer).unwrap())
 453            {
 454                Ok(ix) | Err(ix) => ix,
 455            };
 456            self.0.blocks.insert(
 457                block_ix,
 458                Arc::new(Block {
 459                    id,
 460                    position,
 461                    height: block.height,
 462                    render: Mutex::new(block.render),
 463                    disposition: block.disposition,
 464                }),
 465            );
 466
 467            if let Err(edit_ix) = edits.binary_search_by_key(&start_row, |edit| edit.old.start) {
 468                edits.insert(
 469                    edit_ix,
 470                    Edit {
 471                        old: start_row..end_row,
 472                        new: start_row..end_row,
 473                    },
 474                );
 475            }
 476        }
 477
 478        self.0.sync(wrap_snapshot, edits);
 479        ids
 480    }
 481
 482    pub fn remove(&mut self, block_ids: HashSet<BlockId>) {
 483        let wrap_snapshot = &*self.0.wrap_snapshot.lock();
 484        let buffer = wrap_snapshot.buffer_snapshot();
 485        let mut edits = Vec::new();
 486        let mut last_block_buffer_row = None;
 487        self.0.blocks.retain(|block| {
 488            if block_ids.contains(&block.id) {
 489                let buffer_row = block.position.to_point(&buffer).row;
 490                if last_block_buffer_row != Some(buffer_row) {
 491                    last_block_buffer_row = Some(buffer_row);
 492                    let wrap_row = wrap_snapshot
 493                        .from_point(Point::new(buffer_row, 0), Bias::Left)
 494                        .row();
 495                    let start_row = wrap_snapshot.prev_row_boundary(WrapPoint::new(wrap_row, 0));
 496                    let end_row = wrap_snapshot
 497                        .next_row_boundary(WrapPoint::new(wrap_row, 0))
 498                        .unwrap_or(wrap_snapshot.max_point().row() + 1);
 499                    edits.push(Edit {
 500                        old: start_row..end_row,
 501                        new: start_row..end_row,
 502                    })
 503                }
 504                false
 505            } else {
 506                true
 507            }
 508        });
 509        self.0.sync(wrap_snapshot, edits);
 510    }
 511}
 512
 513impl BlockSnapshot {
 514    #[cfg(test)]
 515    pub fn text(&self) -> String {
 516        self.chunks(0..self.transforms.summary().output_rows, false)
 517            .map(|chunk| chunk.text)
 518            .collect()
 519    }
 520
 521    pub fn chunks<'a>(&'a self, rows: Range<u32>, language_aware: bool) -> BlockChunks<'a> {
 522        let max_output_row = cmp::min(rows.end, self.transforms.summary().output_rows);
 523        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 524        let input_end = {
 525            cursor.seek(&BlockRow(rows.end), Bias::Right, &());
 526            let overshoot = if cursor
 527                .item()
 528                .map_or(false, |transform| transform.is_isomorphic())
 529            {
 530                rows.end - cursor.start().0 .0
 531            } else {
 532                0
 533            };
 534            cursor.start().1 .0 + overshoot
 535        };
 536        let input_start = {
 537            cursor.seek(&BlockRow(rows.start), Bias::Right, &());
 538            let overshoot = if cursor
 539                .item()
 540                .map_or(false, |transform| transform.is_isomorphic())
 541            {
 542                rows.start - cursor.start().0 .0
 543            } else {
 544                0
 545            };
 546            cursor.start().1 .0 + overshoot
 547        };
 548        BlockChunks {
 549            input_chunks: self
 550                .wrap_snapshot
 551                .chunks(input_start..input_end, language_aware),
 552            input_chunk: Default::default(),
 553            transforms: cursor,
 554            output_row: rows.start,
 555            max_output_row,
 556        }
 557    }
 558
 559    pub fn buffer_rows<'a>(&'a self, start_row: u32) -> BlockBufferRows<'a> {
 560        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 561        cursor.seek(&BlockRow(start_row), Bias::Right, &());
 562        let (output_start, input_start) = cursor.start();
 563        let overshoot = if cursor.item().map_or(false, |t| t.is_isomorphic()) {
 564            start_row - output_start.0
 565        } else {
 566            0
 567        };
 568        let input_start_row = input_start.0 + overshoot;
 569        BlockBufferRows {
 570            transforms: cursor,
 571            input_buffer_rows: self.wrap_snapshot.buffer_rows(input_start_row),
 572            output_row: start_row,
 573            started: false,
 574        }
 575    }
 576
 577    pub fn blocks_in_range<'a>(
 578        &'a self,
 579        rows: Range<u32>,
 580    ) -> impl Iterator<Item = (u32, &'a AlignedBlock)> {
 581        let mut cursor = self.transforms.cursor::<BlockRow>();
 582        cursor.seek(&BlockRow(rows.start), Bias::Right, &());
 583        std::iter::from_fn(move || {
 584            while let Some(transform) = cursor.item() {
 585                let start_row = cursor.start().0;
 586                if start_row >= rows.end {
 587                    break;
 588                }
 589                if let Some(block) = &transform.block {
 590                    cursor.next(&());
 591                    return Some((start_row, block));
 592                } else {
 593                    cursor.next(&());
 594                }
 595            }
 596            None
 597        })
 598    }
 599
 600    pub fn max_point(&self) -> BlockPoint {
 601        let row = self.transforms.summary().output_rows - 1;
 602        BlockPoint::new(row, self.line_len(row))
 603    }
 604
 605    pub fn longest_row(&self) -> u32 {
 606        let input_row = self.wrap_snapshot.longest_row();
 607        self.to_block_point(WrapPoint::new(input_row, 0)).row
 608    }
 609
 610    pub fn line_len(&self, row: u32) -> u32 {
 611        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 612        cursor.seek(&BlockRow(row), Bias::Right, &());
 613        if let Some(transform) = cursor.item() {
 614            let (output_start, input_start) = cursor.start();
 615            let overshoot = row - output_start.0;
 616            if transform.block.is_some() {
 617                0
 618            } else {
 619                self.wrap_snapshot.line_len(input_start.0 + overshoot)
 620            }
 621        } else {
 622            panic!("row out of range");
 623        }
 624    }
 625
 626    pub fn is_block_line(&self, row: u32) -> bool {
 627        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 628        cursor.seek(&BlockRow(row), Bias::Right, &());
 629        cursor.item().map_or(false, |t| t.block.is_some())
 630    }
 631
 632    pub fn clip_point(&self, point: BlockPoint, bias: Bias) -> BlockPoint {
 633        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 634        cursor.seek(&BlockRow(point.row), Bias::Right, &());
 635
 636        let max_input_row = WrapRow(self.transforms.summary().input_rows);
 637        let mut search_left =
 638            (bias == Bias::Left && cursor.start().1 .0 > 0) || cursor.end(&()).1 == max_input_row;
 639        let mut reversed = false;
 640
 641        loop {
 642            if let Some(transform) = cursor.item() {
 643                if transform.is_isomorphic() {
 644                    let (output_start_row, input_start_row) = cursor.start();
 645                    let (output_end_row, input_end_row) = cursor.end(&());
 646                    let output_start = Point::new(output_start_row.0, 0);
 647                    let input_start = Point::new(input_start_row.0, 0);
 648                    let input_end = Point::new(input_end_row.0, 0);
 649                    let input_point = if point.row >= output_end_row.0 {
 650                        let line_len = self.wrap_snapshot.line_len(input_end_row.0 - 1);
 651                        self.wrap_snapshot
 652                            .clip_point(WrapPoint::new(input_end_row.0 - 1, line_len), bias)
 653                    } else {
 654                        let output_overshoot = point.0.saturating_sub(output_start);
 655                        self.wrap_snapshot
 656                            .clip_point(WrapPoint(input_start + output_overshoot), bias)
 657                    };
 658
 659                    if (input_start..input_end).contains(&input_point.0) {
 660                        let input_overshoot = input_point.0.saturating_sub(input_start);
 661                        return BlockPoint(output_start + input_overshoot);
 662                    }
 663                }
 664
 665                if search_left {
 666                    cursor.prev(&());
 667                } else {
 668                    cursor.next(&());
 669                }
 670            } else if reversed {
 671                return self.max_point();
 672            } else {
 673                reversed = true;
 674                search_left = !search_left;
 675                cursor.seek(&BlockRow(point.row), Bias::Right, &());
 676            }
 677        }
 678    }
 679
 680    pub fn to_block_point(&self, wrap_point: WrapPoint) -> BlockPoint {
 681        let mut cursor = self.transforms.cursor::<(WrapRow, BlockRow)>();
 682        cursor.seek(&WrapRow(wrap_point.row()), Bias::Right, &());
 683        if let Some(transform) = cursor.item() {
 684            debug_assert!(transform.is_isomorphic());
 685        } else {
 686            return self.max_point();
 687        }
 688
 689        let (input_start_row, output_start_row) = cursor.start();
 690        let input_start = Point::new(input_start_row.0, 0);
 691        let output_start = Point::new(output_start_row.0, 0);
 692        let input_overshoot = wrap_point.0 - input_start;
 693        BlockPoint(output_start + input_overshoot)
 694    }
 695
 696    pub fn to_wrap_point(&self, block_point: BlockPoint) -> WrapPoint {
 697        let mut cursor = self.transforms.cursor::<(BlockRow, WrapRow)>();
 698        cursor.seek(&BlockRow(block_point.row), Bias::Right, &());
 699        if let Some(transform) = cursor.item() {
 700            match transform.block.as_ref().map(|b| b.disposition) {
 701                Some(BlockDisposition::Above) => WrapPoint::new(cursor.start().1 .0, 0),
 702                Some(BlockDisposition::Below) => {
 703                    let wrap_row = cursor.start().1 .0 - 1;
 704                    WrapPoint::new(wrap_row, self.wrap_snapshot.line_len(wrap_row))
 705                }
 706                None => {
 707                    let overshoot = block_point.row - cursor.start().0 .0;
 708                    let wrap_row = cursor.start().1 .0 + overshoot;
 709                    WrapPoint::new(wrap_row, block_point.column)
 710                }
 711            }
 712        } else {
 713            self.wrap_snapshot.max_point()
 714        }
 715    }
 716}
 717
 718impl Transform {
 719    fn isomorphic(rows: u32) -> Self {
 720        Self {
 721            summary: TransformSummary {
 722                input_rows: rows,
 723                output_rows: rows,
 724            },
 725            block: None,
 726        }
 727    }
 728
 729    fn block(block: Arc<Block>, column: u32) -> Self {
 730        Self {
 731            summary: TransformSummary {
 732                input_rows: 0,
 733                output_rows: block.height as u32,
 734            },
 735            block: Some(AlignedBlock { block, column }),
 736        }
 737    }
 738
 739    fn is_isomorphic(&self) -> bool {
 740        self.block.is_none()
 741    }
 742}
 743
 744impl<'a> Iterator for BlockChunks<'a> {
 745    type Item = Chunk<'a>;
 746
 747    fn next(&mut self) -> Option<Self::Item> {
 748        if self.output_row >= self.max_output_row {
 749            return None;
 750        }
 751
 752        let transform = self.transforms.item()?;
 753        if transform.block.is_some() {
 754            let block_start = self.transforms.start().0 .0;
 755            let mut block_end = self.transforms.end(&()).0 .0;
 756            self.transforms.next(&());
 757            if self.transforms.item().is_none() {
 758                block_end -= 1;
 759            }
 760
 761            let start_in_block = self.output_row - block_start;
 762            let end_in_block = cmp::min(self.max_output_row, block_end) - block_start;
 763            let line_count = end_in_block - start_in_block;
 764            self.output_row += line_count;
 765
 766            return Some(Chunk {
 767                text: unsafe { std::str::from_utf8_unchecked(&NEWLINES[..line_count as usize]) },
 768                highlight_id: None,
 769                diagnostic: None,
 770            });
 771        }
 772
 773        if self.input_chunk.text.is_empty() {
 774            if let Some(input_chunk) = self.input_chunks.next() {
 775                self.input_chunk = input_chunk;
 776            } else {
 777                self.output_row += 1;
 778                if self.output_row < self.max_output_row {
 779                    self.transforms.next(&());
 780                    return Some(Chunk {
 781                        text: "\n",
 782                        ..Default::default()
 783                    });
 784                } else {
 785                    return None;
 786                }
 787            }
 788        }
 789
 790        let transform_end = self.transforms.end(&()).0 .0;
 791        let (prefix_rows, prefix_bytes) =
 792            offset_for_row(self.input_chunk.text, transform_end - self.output_row);
 793        self.output_row += prefix_rows;
 794        let (prefix, suffix) = self.input_chunk.text.split_at(prefix_bytes);
 795        self.input_chunk.text = suffix;
 796        if self.output_row == transform_end {
 797            self.transforms.next(&());
 798        }
 799
 800        Some(Chunk {
 801            text: prefix,
 802            ..self.input_chunk
 803        })
 804    }
 805}
 806
 807impl<'a> Iterator for BlockBufferRows<'a> {
 808    type Item = Option<u32>;
 809
 810    fn next(&mut self) -> Option<Self::Item> {
 811        if self.started {
 812            self.output_row += 1;
 813        } else {
 814            self.started = true;
 815        }
 816
 817        if self.output_row >= self.transforms.end(&()).0 .0 {
 818            self.transforms.next(&());
 819        }
 820
 821        let transform = self.transforms.item()?;
 822        if transform.block.is_some() {
 823            Some(None)
 824        } else {
 825            Some(self.input_buffer_rows.next().unwrap())
 826        }
 827    }
 828}
 829
 830impl sum_tree::Item for Transform {
 831    type Summary = TransformSummary;
 832
 833    fn summary(&self) -> Self::Summary {
 834        self.summary.clone()
 835    }
 836}
 837
 838impl sum_tree::Summary for TransformSummary {
 839    type Context = ();
 840
 841    fn add_summary(&mut self, summary: &Self, _: &()) {
 842        self.input_rows += summary.input_rows;
 843        self.output_rows += summary.output_rows;
 844    }
 845}
 846
 847impl<'a> sum_tree::Dimension<'a, TransformSummary> for WrapRow {
 848    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
 849        self.0 += summary.input_rows;
 850    }
 851}
 852
 853impl<'a> sum_tree::Dimension<'a, TransformSummary> for BlockRow {
 854    fn add_summary(&mut self, summary: &'a TransformSummary, _: &()) {
 855        self.0 += summary.output_rows;
 856    }
 857}
 858
 859impl BlockDisposition {
 860    fn is_below(&self) -> bool {
 861        matches!(self, BlockDisposition::Below)
 862    }
 863}
 864
 865impl AlignedBlock {
 866    pub fn height(&self) -> u32 {
 867        self.height as u32
 868    }
 869
 870    pub fn column(&self) -> u32 {
 871        self.column
 872    }
 873
 874    pub fn render(&self, cx: &BlockContext) -> ElementBox {
 875        self.render.lock()(cx)
 876    }
 877
 878    pub fn position(&self) -> &Anchor {
 879        &self.block.position
 880    }
 881}
 882
 883impl Deref for AlignedBlock {
 884    type Target = Block;
 885
 886    fn deref(&self) -> &Self::Target {
 887        self.block.as_ref()
 888    }
 889}
 890
 891impl<'a> Deref for BlockContext<'a> {
 892    type Target = AppContext;
 893
 894    fn deref(&self) -> &Self::Target {
 895        &self.cx
 896    }
 897}
 898
 899impl Debug for Block {
 900    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
 901        f.debug_struct("Block")
 902            .field("id", &self.id)
 903            .field("position", &self.position)
 904            .field("disposition", &self.disposition)
 905            .finish()
 906    }
 907}
 908
 909// Count the number of bytes prior to a target point. If the string doesn't contain the target
 910// point, return its total extent. Otherwise return the target point itself.
 911fn offset_for_row(s: &str, target: u32) -> (u32, usize) {
 912    let mut row = 0;
 913    let mut offset = 0;
 914    for (ix, line) in s.split('\n').enumerate() {
 915        if ix > 0 {
 916            row += 1;
 917            offset += 1;
 918        }
 919        if row >= target {
 920            break;
 921        }
 922        offset += line.len() as usize;
 923    }
 924    (row, offset)
 925}
 926
 927#[cfg(test)]
 928mod tests {
 929    use super::*;
 930    use crate::display_map::{fold_map::FoldMap, tab_map::TabMap, wrap_map::WrapMap};
 931    use crate::multi_buffer::MultiBuffer;
 932    use gpui::{elements::Empty, Element};
 933    use rand::prelude::*;
 934    use std::env;
 935    use text::RandomCharIter;
 936
 937    #[gpui::test]
 938    fn test_offset_for_row() {
 939        assert_eq!(offset_for_row("", 0), (0, 0));
 940        assert_eq!(offset_for_row("", 1), (0, 0));
 941        assert_eq!(offset_for_row("abcd", 0), (0, 0));
 942        assert_eq!(offset_for_row("abcd", 1), (0, 4));
 943        assert_eq!(offset_for_row("\n", 0), (0, 0));
 944        assert_eq!(offset_for_row("\n", 1), (1, 1));
 945        assert_eq!(offset_for_row("abc\ndef\nghi", 0), (0, 0));
 946        assert_eq!(offset_for_row("abc\ndef\nghi", 1), (1, 4));
 947        assert_eq!(offset_for_row("abc\ndef\nghi", 2), (2, 8));
 948        assert_eq!(offset_for_row("abc\ndef\nghi", 3), (2, 11));
 949    }
 950
 951    #[gpui::test]
 952    fn test_basic_blocks(cx: &mut gpui::MutableAppContext) {
 953        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
 954        let font_id = cx
 955            .font_cache()
 956            .select_font(family_id, &Default::default())
 957            .unwrap();
 958
 959        let text = "aaa\nbbb\nccc\nddd";
 960
 961        let buffer = MultiBuffer::build_simple(text, cx);
 962        let buffer_snapshot = buffer.read(cx).snapshot(cx);
 963        let subscription = buffer.update(cx, |buffer, _| buffer.subscribe());
 964        let (fold_map, folds_snapshot) = FoldMap::new(buffer_snapshot.clone());
 965        let (tab_map, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), 1);
 966        let (wrap_map, wraps_snapshot) = WrapMap::new(tabs_snapshot, font_id, 14.0, None, cx);
 967        let mut block_map = BlockMap::new(wraps_snapshot.clone());
 968
 969        let mut writer = block_map.write(wraps_snapshot.clone(), vec![]);
 970        writer.insert(vec![
 971            BlockProperties {
 972                position: buffer_snapshot.anchor_after(Point::new(1, 0)),
 973                height: 1,
 974                disposition: BlockDisposition::Above,
 975                render: Arc::new(|_| Empty::new().named("block 1")),
 976            },
 977            BlockProperties {
 978                position: buffer_snapshot.anchor_after(Point::new(1, 2)),
 979                height: 2,
 980                disposition: BlockDisposition::Above,
 981                render: Arc::new(|_| Empty::new().named("block 2")),
 982            },
 983            BlockProperties {
 984                position: buffer_snapshot.anchor_after(Point::new(3, 3)),
 985                height: 3,
 986                disposition: BlockDisposition::Below,
 987                render: Arc::new(|_| Empty::new().named("block 3")),
 988            },
 989        ]);
 990
 991        let snapshot = block_map.read(wraps_snapshot, vec![]);
 992        assert_eq!(snapshot.text(), "aaa\n\n\n\nbbb\nccc\nddd\n\n\n");
 993
 994        let blocks = snapshot
 995            .blocks_in_range(0..8)
 996            .map(|(start_row, block)| {
 997                (
 998                    start_row..start_row + block.height(),
 999                    block.column(),
1000                    block
1001                        .render(&BlockContext {
1002                            cx,
1003                            anchor_x: 0.,
1004                            gutter_padding: 0.,
1005                            scroll_x: 0.,
1006                            gutter_width: 0.,
1007                            line_height: 0.,
1008                            em_width: 0.,
1009                        })
1010                        .name()
1011                        .unwrap()
1012                        .to_string(),
1013                )
1014            })
1015            .collect::<Vec<_>>();
1016
1017        // When multiple blocks are on the same line, the newer blocks appear first.
1018        assert_eq!(
1019            blocks,
1020            &[
1021                (1..3, 2, "block 2".to_string()),
1022                (3..4, 0, "block 1".to_string()),
1023                (7..10, 3, "block 3".to_string()),
1024            ]
1025        );
1026
1027        assert_eq!(
1028            snapshot.to_block_point(WrapPoint::new(0, 3)),
1029            BlockPoint::new(0, 3)
1030        );
1031        assert_eq!(
1032            snapshot.to_block_point(WrapPoint::new(1, 0)),
1033            BlockPoint::new(4, 0)
1034        );
1035        assert_eq!(
1036            snapshot.to_block_point(WrapPoint::new(3, 3)),
1037            BlockPoint::new(6, 3)
1038        );
1039
1040        assert_eq!(
1041            snapshot.to_wrap_point(BlockPoint::new(0, 3)),
1042            WrapPoint::new(0, 3)
1043        );
1044        assert_eq!(
1045            snapshot.to_wrap_point(BlockPoint::new(1, 0)),
1046            WrapPoint::new(1, 0)
1047        );
1048        assert_eq!(
1049            snapshot.to_wrap_point(BlockPoint::new(3, 0)),
1050            WrapPoint::new(1, 0)
1051        );
1052        assert_eq!(
1053            snapshot.to_wrap_point(BlockPoint::new(7, 0)),
1054            WrapPoint::new(3, 3)
1055        );
1056
1057        assert_eq!(
1058            snapshot.clip_point(BlockPoint::new(1, 0), Bias::Left),
1059            BlockPoint::new(0, 3)
1060        );
1061        assert_eq!(
1062            snapshot.clip_point(BlockPoint::new(1, 0), Bias::Right),
1063            BlockPoint::new(4, 0)
1064        );
1065        assert_eq!(
1066            snapshot.clip_point(BlockPoint::new(1, 1), Bias::Left),
1067            BlockPoint::new(0, 3)
1068        );
1069        assert_eq!(
1070            snapshot.clip_point(BlockPoint::new(1, 1), Bias::Right),
1071            BlockPoint::new(4, 0)
1072        );
1073        assert_eq!(
1074            snapshot.clip_point(BlockPoint::new(4, 0), Bias::Left),
1075            BlockPoint::new(4, 0)
1076        );
1077        assert_eq!(
1078            snapshot.clip_point(BlockPoint::new(4, 0), Bias::Right),
1079            BlockPoint::new(4, 0)
1080        );
1081        assert_eq!(
1082            snapshot.clip_point(BlockPoint::new(6, 3), Bias::Left),
1083            BlockPoint::new(6, 3)
1084        );
1085        assert_eq!(
1086            snapshot.clip_point(BlockPoint::new(6, 3), Bias::Right),
1087            BlockPoint::new(6, 3)
1088        );
1089        assert_eq!(
1090            snapshot.clip_point(BlockPoint::new(7, 0), Bias::Left),
1091            BlockPoint::new(6, 3)
1092        );
1093        assert_eq!(
1094            snapshot.clip_point(BlockPoint::new(7, 0), Bias::Right),
1095            BlockPoint::new(6, 3)
1096        );
1097
1098        assert_eq!(
1099            snapshot.buffer_rows(0).collect::<Vec<_>>(),
1100            &[
1101                Some(0),
1102                None,
1103                None,
1104                None,
1105                Some(1),
1106                Some(2),
1107                Some(3),
1108                None,
1109                None,
1110                None
1111            ]
1112        );
1113
1114        // Insert a line break, separating two block decorations into separate lines.
1115        let buffer_snapshot = buffer.update(cx, |buffer, cx| {
1116            buffer.edit([Point::new(1, 1)..Point::new(1, 1)], "!!!\n", cx);
1117            buffer.snapshot(cx)
1118        });
1119
1120        let (folds_snapshot, fold_edits) =
1121            fold_map.read(buffer_snapshot, subscription.consume().into_inner());
1122        let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1123        let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1124            wrap_map.sync(tabs_snapshot, tab_edits, cx)
1125        });
1126        let snapshot = block_map.read(wraps_snapshot, wrap_edits);
1127        assert_eq!(snapshot.text(), "aaa\n\nb!!!\n\n\nbb\nccc\nddd\n\n\n");
1128    }
1129
1130    #[gpui::test]
1131    fn test_blocks_on_wrapped_lines(cx: &mut gpui::MutableAppContext) {
1132        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
1133        let font_id = cx
1134            .font_cache()
1135            .select_font(family_id, &Default::default())
1136            .unwrap();
1137
1138        let text = "one two three\nfour five six\nseven eight";
1139
1140        let buffer = MultiBuffer::build_simple(text, cx);
1141        let buffer_snapshot = buffer.read(cx).snapshot(cx);
1142        let (_, folds_snapshot) = FoldMap::new(buffer_snapshot.clone());
1143        let (_, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), 1);
1144        let (_, wraps_snapshot) = WrapMap::new(tabs_snapshot, font_id, 14.0, Some(60.), cx);
1145        let mut block_map = BlockMap::new(wraps_snapshot.clone());
1146
1147        let mut writer = block_map.write(wraps_snapshot.clone(), vec![]);
1148        writer.insert(vec![
1149            BlockProperties {
1150                position: buffer_snapshot.anchor_after(Point::new(1, 12)),
1151                disposition: BlockDisposition::Above,
1152                render: Arc::new(|_| Empty::new().named("block 1")),
1153                height: 1,
1154            },
1155            BlockProperties {
1156                position: buffer_snapshot.anchor_after(Point::new(1, 1)),
1157                disposition: BlockDisposition::Below,
1158                render: Arc::new(|_| Empty::new().named("block 2")),
1159                height: 1,
1160            },
1161        ]);
1162
1163        // Blocks with an 'above' disposition go above their corresponding buffer line.
1164        // Blocks with a 'below' disposition go below their corresponding buffer line.
1165        let snapshot = block_map.read(wraps_snapshot, vec![]);
1166        assert_eq!(
1167            snapshot.text(),
1168            "one two \nthree\n\nfour five \nsix\n\nseven \neight"
1169        );
1170    }
1171
1172    #[gpui::test(iterations = 100)]
1173    fn test_random_blocks(cx: &mut gpui::MutableAppContext, mut rng: StdRng) {
1174        let operations = env::var("OPERATIONS")
1175            .map(|i| i.parse().expect("invalid `OPERATIONS` variable"))
1176            .unwrap_or(10);
1177
1178        let wrap_width = if rng.gen_bool(0.2) {
1179            None
1180        } else {
1181            Some(rng.gen_range(0.0..=100.0))
1182        };
1183        let tab_size = 1;
1184        let family_id = cx.font_cache().load_family(&["Helvetica"]).unwrap();
1185        let font_id = cx
1186            .font_cache()
1187            .select_font(family_id, &Default::default())
1188            .unwrap();
1189        let font_size = 14.0;
1190
1191        log::info!("Wrap width: {:?}", wrap_width);
1192
1193        let buffer = if rng.gen() {
1194            let len = rng.gen_range(0..10);
1195            let text = RandomCharIter::new(&mut rng).take(len).collect::<String>();
1196            log::info!("initial buffer text: {:?}", text);
1197            MultiBuffer::build_simple(&text, cx)
1198        } else {
1199            MultiBuffer::build_random(&mut rng, cx)
1200        };
1201
1202        let mut buffer_snapshot = buffer.read(cx).snapshot(cx);
1203        let (fold_map, folds_snapshot) = FoldMap::new(buffer_snapshot.clone());
1204        let (tab_map, tabs_snapshot) = TabMap::new(folds_snapshot.clone(), tab_size);
1205        let (wrap_map, wraps_snapshot) =
1206            WrapMap::new(tabs_snapshot, font_id, font_size, wrap_width, cx);
1207        let mut block_map = BlockMap::new(wraps_snapshot);
1208        let mut expected_blocks = Vec::new();
1209
1210        for _ in 0..operations {
1211            let mut buffer_edits = Vec::new();
1212            match rng.gen_range(0..=100) {
1213                0..=19 => {
1214                    let wrap_width = if rng.gen_bool(0.2) {
1215                        None
1216                    } else {
1217                        Some(rng.gen_range(0.0..=100.0))
1218                    };
1219                    log::info!("Setting wrap width to {:?}", wrap_width);
1220                    wrap_map.update(cx, |map, cx| map.set_wrap_width(wrap_width, cx));
1221                }
1222                20..=39 => {
1223                    let block_count = rng.gen_range(1..=5);
1224                    let block_properties = (0..block_count)
1225                        .map(|_| {
1226                            let buffer = buffer.read(cx).read(cx);
1227                            let position = buffer.anchor_after(
1228                                buffer.clip_offset(rng.gen_range(0..=buffer.len()), Bias::Left),
1229                            );
1230
1231                            let disposition = if rng.gen() {
1232                                BlockDisposition::Above
1233                            } else {
1234                                BlockDisposition::Below
1235                            };
1236                            let height = rng.gen_range(1..5);
1237                            log::info!(
1238                                "inserting block {:?} {:?} with height {}",
1239                                disposition,
1240                                position.to_point(&buffer),
1241                                height
1242                            );
1243                            BlockProperties {
1244                                position,
1245                                height,
1246                                disposition,
1247                                render: Arc::new(|_| Empty::new().boxed()),
1248                            }
1249                        })
1250                        .collect::<Vec<_>>();
1251
1252                    let (folds_snapshot, fold_edits) =
1253                        fold_map.read(buffer_snapshot.clone(), vec![]);
1254                    let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1255                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1256                        wrap_map.sync(tabs_snapshot, tab_edits, cx)
1257                    });
1258                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits);
1259                    let block_ids = block_map.insert(block_properties.clone());
1260                    for (block_id, props) in block_ids.into_iter().zip(block_properties) {
1261                        expected_blocks.push((block_id, props));
1262                    }
1263                }
1264                40..=59 if !expected_blocks.is_empty() => {
1265                    let block_count = rng.gen_range(1..=4.min(expected_blocks.len()));
1266                    let block_ids_to_remove = (0..block_count)
1267                        .map(|_| {
1268                            expected_blocks
1269                                .remove(rng.gen_range(0..expected_blocks.len()))
1270                                .0
1271                        })
1272                        .collect();
1273
1274                    let (folds_snapshot, fold_edits) =
1275                        fold_map.read(buffer_snapshot.clone(), vec![]);
1276                    let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1277                    let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1278                        wrap_map.sync(tabs_snapshot, tab_edits, cx)
1279                    });
1280                    let mut block_map = block_map.write(wraps_snapshot, wrap_edits);
1281                    block_map.remove(block_ids_to_remove);
1282                }
1283                _ => {
1284                    buffer.update(cx, |buffer, cx| {
1285                        let edit_count = rng.gen_range(1..=5);
1286                        let subscription = buffer.subscribe();
1287                        buffer.randomly_edit(&mut rng, edit_count, cx);
1288                        buffer_snapshot = buffer.snapshot(cx);
1289                        buffer_edits.extend(subscription.consume());
1290                        log::info!("buffer text: {:?}", buffer_snapshot.text());
1291                    });
1292                }
1293            }
1294
1295            let (folds_snapshot, fold_edits) = fold_map.read(buffer_snapshot.clone(), buffer_edits);
1296            let (tabs_snapshot, tab_edits) = tab_map.sync(folds_snapshot, fold_edits);
1297            let (wraps_snapshot, wrap_edits) = wrap_map.update(cx, |wrap_map, cx| {
1298                wrap_map.sync(tabs_snapshot, tab_edits, cx)
1299            });
1300            let blocks_snapshot = block_map.read(wraps_snapshot.clone(), wrap_edits);
1301            assert_eq!(
1302                blocks_snapshot.transforms.summary().input_rows,
1303                wraps_snapshot.max_point().row() + 1
1304            );
1305            log::info!("blocks text: {:?}", blocks_snapshot.text());
1306
1307            let mut sorted_blocks = expected_blocks
1308                .iter()
1309                .cloned()
1310                .map(|(id, block)| {
1311                    let mut position = block.position.to_point(&buffer_snapshot);
1312                    let column = wraps_snapshot.from_point(position, Bias::Left).column();
1313                    match block.disposition {
1314                        BlockDisposition::Above => {
1315                            position.column = 0;
1316                        }
1317                        BlockDisposition::Below => {
1318                            position.column = buffer_snapshot.line_len(position.row);
1319                        }
1320                    };
1321                    let row = wraps_snapshot.from_point(position, Bias::Left).row();
1322                    (
1323                        id,
1324                        BlockProperties {
1325                            position: BlockPoint::new(row, column),
1326                            height: block.height,
1327                            disposition: block.disposition,
1328                            render: block.render.clone(),
1329                        },
1330                    )
1331                })
1332                .collect::<Vec<_>>();
1333            sorted_blocks.sort_unstable_by_key(|(id, block)| {
1334                (block.position.row, block.disposition, Reverse(*id))
1335            });
1336            let mut sorted_blocks_iter = sorted_blocks.iter().peekable();
1337
1338            let input_buffer_rows = buffer_snapshot.buffer_rows(0).collect::<Vec<_>>();
1339            let mut expected_buffer_rows = Vec::new();
1340            let mut expected_text = String::new();
1341            let mut expected_block_positions = Vec::new();
1342            let input_text = wraps_snapshot.text();
1343            for (row, input_line) in input_text.split('\n').enumerate() {
1344                let row = row as u32;
1345                if row > 0 {
1346                    expected_text.push('\n');
1347                }
1348
1349                let buffer_row = input_buffer_rows[wraps_snapshot
1350                    .to_point(WrapPoint::new(row, 0), Bias::Left)
1351                    .row as usize];
1352
1353                while let Some((block_id, block)) = sorted_blocks_iter.peek() {
1354                    if block.position.row == row && block.disposition == BlockDisposition::Above {
1355                        expected_block_positions
1356                            .push((expected_text.matches('\n').count() as u32, *block_id));
1357                        let text = "\n".repeat(block.height as usize);
1358                        expected_text.push_str(&text);
1359                        for _ in 0..block.height {
1360                            expected_buffer_rows.push(None);
1361                        }
1362                        sorted_blocks_iter.next();
1363                    } else {
1364                        break;
1365                    }
1366                }
1367
1368                let soft_wrapped = wraps_snapshot.to_tab_point(WrapPoint::new(row, 0)).column() > 0;
1369                expected_buffer_rows.push(if soft_wrapped { None } else { buffer_row });
1370                expected_text.push_str(input_line);
1371
1372                while let Some((block_id, block)) = sorted_blocks_iter.peek() {
1373                    if block.position.row == row && block.disposition == BlockDisposition::Below {
1374                        expected_block_positions
1375                            .push((expected_text.matches('\n').count() as u32 + 1, *block_id));
1376                        let text = "\n".repeat(block.height as usize);
1377                        expected_text.push_str(&text);
1378                        for _ in 0..block.height {
1379                            expected_buffer_rows.push(None);
1380                        }
1381                        sorted_blocks_iter.next();
1382                    } else {
1383                        break;
1384                    }
1385                }
1386            }
1387
1388            let expected_lines = expected_text.split('\n').collect::<Vec<_>>();
1389            let expected_row_count = expected_lines.len();
1390            for start_row in 0..expected_row_count {
1391                let expected_text = expected_lines[start_row..].join("\n");
1392                let actual_text = blocks_snapshot
1393                    .chunks(start_row as u32..expected_row_count as u32, false)
1394                    .map(|chunk| chunk.text)
1395                    .collect::<String>();
1396                assert_eq!(
1397                    actual_text, expected_text,
1398                    "incorrect text starting from row {}",
1399                    start_row
1400                );
1401                assert_eq!(
1402                    blocks_snapshot
1403                        .buffer_rows(start_row as u32)
1404                        .collect::<Vec<_>>(),
1405                    &expected_buffer_rows[start_row..]
1406                );
1407            }
1408
1409            assert_eq!(
1410                blocks_snapshot
1411                    .blocks_in_range(0..(expected_row_count as u32))
1412                    .map(|(row, block)| (row, block.id))
1413                    .collect::<Vec<_>>(),
1414                expected_block_positions
1415            );
1416
1417            let mut expected_longest_rows = Vec::new();
1418            let mut longest_line_len = -1_isize;
1419            for (row, line) in expected_lines.iter().enumerate() {
1420                let row = row as u32;
1421
1422                assert_eq!(
1423                    blocks_snapshot.line_len(row),
1424                    line.len() as u32,
1425                    "invalid line len for row {}",
1426                    row
1427                );
1428
1429                let line_char_count = line.chars().count() as isize;
1430                match line_char_count.cmp(&longest_line_len) {
1431                    Ordering::Less => {}
1432                    Ordering::Equal => expected_longest_rows.push(row),
1433                    Ordering::Greater => {
1434                        longest_line_len = line_char_count;
1435                        expected_longest_rows.clear();
1436                        expected_longest_rows.push(row);
1437                    }
1438                }
1439            }
1440
1441            let longest_row = blocks_snapshot.longest_row();
1442            assert!(
1443                expected_longest_rows.contains(&longest_row),
1444                "incorrect longest row {}. expected {:?} with length {}",
1445                longest_row,
1446                expected_longest_rows,
1447                longest_line_len,
1448            );
1449
1450            for row in 0..=blocks_snapshot.wrap_snapshot.max_point().row() {
1451                let wrap_point = WrapPoint::new(row, 0);
1452                let block_point = blocks_snapshot.to_block_point(wrap_point);
1453                assert_eq!(blocks_snapshot.to_wrap_point(block_point), wrap_point);
1454            }
1455
1456            let mut block_point = BlockPoint::new(0, 0);
1457            for c in expected_text.chars() {
1458                let left_point = blocks_snapshot.clip_point(block_point, Bias::Left);
1459                let left_buffer_point = blocks_snapshot.to_point(left_point, Bias::Left);
1460                assert_eq!(
1461                    blocks_snapshot.to_block_point(blocks_snapshot.to_wrap_point(left_point)),
1462                    left_point
1463                );
1464                assert_eq!(
1465                    left_buffer_point,
1466                    buffer_snapshot.clip_point(left_buffer_point, Bias::Right),
1467                    "{:?} is not valid in buffer coordinates",
1468                    left_point
1469                );
1470
1471                let right_point = blocks_snapshot.clip_point(block_point, Bias::Right);
1472                let right_buffer_point = blocks_snapshot.to_point(right_point, Bias::Right);
1473                assert_eq!(
1474                    blocks_snapshot.to_block_point(blocks_snapshot.to_wrap_point(right_point)),
1475                    right_point
1476                );
1477                assert_eq!(
1478                    right_buffer_point,
1479                    buffer_snapshot.clip_point(right_buffer_point, Bias::Left),
1480                    "{:?} is not valid in buffer coordinates",
1481                    right_point
1482                );
1483
1484                if c == '\n' {
1485                    block_point.0 += Point::new(1, 0);
1486                } else {
1487                    block_point.column += c.len_utf8() as u32;
1488                }
1489            }
1490        }
1491    }
1492
1493    impl BlockSnapshot {
1494        fn to_point(&self, point: BlockPoint, bias: Bias) -> Point {
1495            self.wrap_snapshot.to_point(self.to_wrap_point(point), bias)
1496        }
1497    }
1498}